Background and objective: Patients with spinal cord injury suffer from neurogenic lower urinary tract dysfunction (NLUTD). NLUTD is associated with a considerable morbidity and mortality, but also affects the quality of life (QoL). We aimed to evaluate the longitudinal course of QoL in persons with NLUTD in relation to their bladder management.Subjects and methods: In a prospective self-controlled case series study. Patients with chronic NLUTD managing their bladder either by intermittent catheterization (n = 21), reflex voiding (n = 8), anterior root stimulation (n = 7), straining (n = 7) or suprapubic catheter (n = 4) were asked to fill in the Qualiveen® questionnaire at two time points with a time span of at least 1 year. Eleven patients were tetraplegic, and 36 persons suffered from paraplegia. The study was approved by the Ethics Committee of the Ethikkommission Nordwestund Zentralschweiz (approval No. PB_2016-02657) on September 24, 2007. Results: In total 47 patients returned both questionnaires and their data were therefore evaluated. The mean age at the first evaluation was 52 ± 12.8 years. The mean duration of NLUTD was 20.4 ± 12.3 years. A mean 2.4 ± 0.5 years had elapsed from the first to the second evaluation. None of the Qualiveen questionnaire domains showed a significant change between the two evaluation time points. The lesion level had a significant (P ≤ 0.023) effect on the domains constraints and QoL index.Conclusion: QoL in patients with chronic NLUTD seems to remain stable in long-term follow-up.Trial registration: ClinicalTrials.gov (NCT02179073) on July 1, 2014.

Virtually every patient with spinal cord injury (SCI) suffers from neurogenic lower urinary tract dysfunction (NLUTD). Especially suprasacral SCI frequently leads to elevated bladder storage pressures which are the major risk factor for renal deterioration (Gerridzen et al., 1992). The impaired storage and voiding functions of the lower urinary tract are clinically relevant risk factors for renal damage (Gerridzen et al., 1992). NLUTD is not only associated with a considerable morbidity and mortality, but may also cause symptoms, such as incontinence, urinary retention and urinary tract infections, which substantially affect the quality of life (QoL) (Biering-Sorensen et al., 1999).

Initial studies have demonstrated that the Qualiveen® (Coloplast, Denmark) questionnaire is a useful tool to measure QoL in relation to bladder dysfunction in persons with NLUTD (Costa et al., 2001; Clark and Welk, 2016). Especially in patients with SCI, it has been proven to be specific for urologic problems (Hill et al, 2010). However, long-term data evaluating the QoL in patients with NLUTD over time are scarce. Therefore, we aimed to evaluate the longitudinal course of the Qualiveen scores in persons with NLUTD.

Participants and Methods

Participants

In a prospective study, 100 consecutive patients with NLUTD in 2014 for an urodynamic examination were asked to participate in the study. Eighty patients agreed and were included after having signed the informed consent form (Additional file 1) [Additional file 1]. Inclusion criteria were: age above 18 years, urodynamically proven NLUTD existing for at least 1 year, mental ability to understand and fill out the questionnaire. Exclusion criteria were inability to fill out the questionnaire, either due to insufficient understanding or lack of knowledge of German.

Methods

Participants filled out the German version of the Qualiveen® (Coloplast, Denmark) questionnaire, which is available in a validated version (Pannek et al., 2007). The questionnaire consists of 30 questions covering four domains: bother with limitations (nine items), frequency of limitations (eight items), fears (eight items), and feelings (five items). Response options are given on a scale from 0 to 4. The scores decrease when problems increase. All participants were asked to fill in the same questionnaire at the next urodynamic routine control visit. The study was approved by the Ethics Committee of the Ethikkommission Nordwestund Zentralschweiz (approval No. PB_2016-02657) on September 24, 2007 (Additional file 2) [Additional file 2].

Statistical analysis

The data were calculated as mean and standard deviation or median and 95% confidence interval based on the distribution of the analyzed data.

The effects of gender, evacuation method (intermittent catheterization/other methods), lesion level (tetraplegia/paraplegia) and time (first evaluation/follow-up evaluation) on Qualiveen parameters were investigated using the Brunner method for the nonparametric (rank-based) analysis of longitudinal data in factorial designs. For the evaluation of the bladder evacuation method, the data of individuals using suprapubic catheterization (SPC) were excluded from analyses due to the small sample size (i.e., n = 4). The Wilcoxon signed-rank test and the Wilcoxon rank-sum test were used to investigate the differences of a specific parameter between the time points and the groups at the specific time points, respectively. The statistical analyses were performed using the R software environment (Version 3.5.0, Copyright 2018, The R Foundation for Statistical Computing, Auckland, New Zealand) and the package “nparLD” (The R Foundation for Statistical Computing, Auckland, New Zealand) as well as the SPSS software (Version 25, IBM, Armonk, NY, USA). A P value of ≤ 0.05 was considered significant.

Results

Patient characteristics

Of the 80 patients that filled in the initial questionnaire, 47 returned the second Qualiveen form. The characteristics of the 47 evaluated patients are presented in [Table 1]. The mean age at the first and second evaluation was 52 ± 12.8 years (range 24–76 years) and 54.2 ± 12.8 years (range 26–79 years), respectively. The mean duration of NLUTD was 20.4 ± 12.3 years (range 1.7–44.5 years) and 22.8 ± 12.2 years (range 4.5–47.2 years) at the first and second evaluation, respectively. A mean 2.4 ± 0.5 years (range 0.8–3.1 years) had elapsed from the first to the second evaluation.

The Qualiveen data at first and the follow-up evaluation time point are presented in [Table 2]. None of the questionnaire domains showed a significant (P > 0.05) change between the two evaluation time points.

Table 2: Qualiveen data at the first and the follow-up evaluation time point

The changes over time in the domains limitations and QoL index were significantly (P ≤ 0.044) different between women and men (Additional Table 1) [Additional file 3]. Furthermore, the lesion level had a significant (P ≤ 0.023) effect on the domains constraints and QoL index (Additional Table 1). [Table 3] shows the Qualiveen data for the evaluated factors. The QoL index in women was significantly (P = 0.05) greater at the follow-up evaluation compared to the first evaluation [Table 3]. At the first evaluation time-point, the values for the domains constraints and QoL index were significantly (P = 0.013) greater and smaller, respectively, in individuals with tetraplegia [Table 3].

Table 3: Qualiveen data presented for the evaluated factors in the included 47 patients

To our knowledge, our study is the first to evaluate the long-term development of QoL with regard to NLUTD symptoms. We found a statistically significant difference between the different bladder management techniques, neither at a given time point nor over time.

As there are no other studies evaluating the long-term development of QoL in relation to bladder management, comparison is only possible with data from cross-sectional evaluations of QoL. These studies, however, demonstrated a significant impact of bladder management on QoL. Adriaansen et al. (2017) described that indwelling transurethral catheters had the highest negative impact on QoL in patients with NLUTD due to chronic SCI. In our study, there were no persons with transurethral catheters and all persons with SPC were excluded from analysis. Other studies using the Qualiveen questionnaire demonstrated that a treatment regimen leading to favorable urodynamic results and continence correlated with better QoL (Pannek and Kullik, 2009).

The ultimate goal of NLUTD treatment is the preservation of renal function (Groen et al., 2016). Due to medical advances, the life expectancy of persons with SCI has dramatically improved over time (Savic et al., 2017a), and urologic complications are not the primary cause of death anymore (Savic et al., 2017b). Having established a level of care that enables long-term survival, QoL becomes increasingly important for both patients and caregivers. Bladder problems remain to be frequent and to have a negative impact both on health status and on QoL in persons with SCI (Adriaansen et al., 2017; Park et al., 2017). Therefore, the study addresses a relevant problem which significantly influences the daily life of patients with chronic SCI.

Several questionnaires have been used to assess QoL due to NLUTD in patients with SCI. The Urogenital Distress Inventory short form 6 was developed to assess the impact of urinary incontinence on QoL (Uebersax et al., 1995). However, item development was not specific to SCI. The International Consultation on Incontinence Modular Questionnaire assesses the impact of urinary incontinence on QoL (Abrams et al., 2006), but is neither NLUTD specific nor does it cover other forms of bladder dysfunction than incontinence. Additional tools, namely the Spinal Cord Injury-Quality of Life Bladder Complications Scale and the Spinal Cord Injury-Quality of Life Bladder Management Difficulties (Tulsky et al., 2015) were also developed specifically to assess QoL related to neurogenic bladder in SCI, but have not yet been used in clinical studies. In a recent systematic review, the Quality of Life Index and the Qualiveen questionnaire were found to be the only validated SCI-specific tools that showed sensitivity to the effects of neurogenic bladder (Best et al., 2017). The Qualiveen is a 30-item questionnaire that was developed to assess QoL in relation to NLUTD symptoms. Initially published in 2001 (Costa et al., 2001), it has been translated and validated in several languages, including German (Pannek et al., 2007). It has been proven to detect clinically meaningful differences (Bonniaud et al., 2008a). Thus, the choice of the Qualiveen for the assessment of QoL seems to be well justified.

Drawbacks of our study are the small number of participants and the low percentage of persons returning both questionnaires. Meanwhile, a short form of the Qualiveen questionnaire has been published, which may increase the number of patients willing to fill it out, as it is less time consuming (Bonniaud et al., 2008b). The short form has been validated in different languages (Reuvers et al., 2017), but not yet in German. We therefore had to use the long version, which may have contributed to the low response rate in our study. The relatively small number of patients makes it difficult to perform a meaningful analysis of subgroups, which may explain the differences between our results and the previously published studies. However, the absolute number of patients seems adequate to evaluate the QoL over time, especially as the vast majority of patients did not alter their bladder regime over time.

Conclusion

QoL in patients with chronic NLUTD seems to remain stable in long-term follow-up, irrespective of the type of bladder management.

Concept and design of study protocol and data collection: JK and JW; drafting of the manuscript: JP. All authors approved the final manuscript for publication.

Conflicts of interest

The authors have no conflicts of interest to declare.

Financial support

None.

Institutional review board statement

The study protocol was approved by Ethics Committee of the Ethics Committee of the Ethikkommission Nordwestund Zentralschweiz (approval No. PB_2016-02657) on September 24, 2007. This study was performed according to the statement of the Declaration of Helsinki, and informed consent of the study procedure was obtained from all participants.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the forms, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity.

Reporting statement

This study followed the Recommendations for the Conduct, Reporting, Editing and Publication of Scholarly Work in Medical Journals developed by the International Committee of Medical Journal Editors.Biostatistics statement

The statistical methods of this study were reviewed by the biostatistician of Swiss Paraplegic Centre, Switzerland.

Copyright license agreement

The Copyright License Agreement has been signed by all authors before publication.

Data sharing statement

Individual participant data that underlie the results reported in this article, after deidentification (text, tables, figures, and appendices). Study protocol and informed consent form will be available immediately following publication, without end date. Results will be disseminated through presentations at scientific meetings and/or by publication in a peer-reviewed journal. Anonymized trial data will be available indefinitely at www.figshare.com.

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Open access statement

This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.

Pannek J, Märk R, Stöhrer M, Schurch B (2007) Quality of life in German-speaking patients with spinal cord injuries and bladder dysfunctions. Validation of the German version of the Qualiveen questionnaire. Urologe A 46:1416-1421.